Since their introduction, printers have become very popular peripherals for computers. One type of printer is the laser printer. In a laser printer, a laser scans an image onto a charged drum, which is coated with toner where the laser scanned the image. The image is developed with the toner, and is transferred to the media. A fuser, generally located in the printer, then fuses the toner permanently to the media. Laser printers, as well as other types of printers, are commonly available in both monochrome models and color models.
The laser-scanning mechanism of a laser printer is quite complex. The mechanism usually includes an elaborate combination of rotating mirrors and lenses to scan the laser from one end of the drum to the other end of the drum. These parts may occupy a large amount of space within the printer, increasing the printer's size and/or footprint. Furthermore, the parts may have to be shielded against unwanted vibrations, requiring additional design expense and also raising manufacturing costs.
The rotating mirror may have to rotate in excess of 30,000 revolutions-per-minute for the printer to achieve high-speed printing, since the drum is discharged serially. To obtain high image quality, the scanning mechanism may have to be manufactured to a high degree of tolerance, which also increases manufacturing costs. If the laser-scanning mechanism fails, the entire printer fails, since the drum cannot then be properly discharged. Even if the scanning mechanism does not catastrophically fail, improper operation or improper alignment of the mechanism can cause image quality to suffer.